Fundamentals of fundamental particles

This month's Scientific American has an article suggesting that a proton's radius might not be known to an accuracy which was previously assumed. In all our chemistry and physics books we have all sorts of values for all sorts of masses, radii etc. Each to a seemingly razor (a very tiny one) sharp accuracy. This recent article suggests that while the group of scientists went in thinking they were improving the accuracy of the proton radius, they obtain much different results.

They claim that the odds of it being a mistake are quite slim.
One interesting part of info in this article says that electrons have a non zero probability of existing -inside- the proton because of their wave nature. It would be useful, then, to know the radius of a proton so that you can determine the effects inner electrons have when their are within or very close to the proton. The researchers used particles called muons to measure the radius by bombarding it and measuring the wavelengths of virtual (I don't understand virtual particles) photons emitted. They used muons because they seem to spend more time within the proton according to their wave function and make it easier to measure the proton radius. They used very specific energy levels that should exist for electrons in certain orbitals. The author describes changing the 'atom's' energy state from 2s to 2p, but we were taught that it was the electron that moved to that state. Maybe it's just phrasing.

The wave function view of an atom is thought to better describe and predict behavior of small particles.

Taken from: http://faculty.wcas.northwestern.edu

Anyhow, it's neat to see there are still very fundamental properties being discovered. I think discoveries like this are great for moral in the sciences because they show the scientific method and verification works. Many of us could discover new useful and interesting biological interactions in our studies and work.

Another recent fundamental discovery involved creating stem cells by adding acids to normal cells in mice. Whether we directly contribute to new discoveries or simply verify existing theories, it's all useful to our society. This semester I hope to work with any type of genetic analysis so that I can explore the large field of DNA analysis, evolution and how it ties in to disease. Also of interest to me is human microbiome and it's relation to health.


This article can be viewed through ebsco at our library in the February 2014 Scientific American:

The Proton Radius Problem. By: Bernauer, Jan C., Pohl, Randolf, Scientific American, 00368733, Feb2014, Vol. 310, Issue 2